That is what the Commons Environmental Audit Committee has done. Despite coming from a body dominated by Conservatives, its highly critical new report warns that the loosening of planning regulations contained in the National Planning Policy Framework is “contradictory and confusing”.

This is an argument that has been rumbling away since July when the Coalition’s proposals referred to a “presumption in favour” of development. Then the National Trust warned that this could lead to “unchecked and damaging development”. The committee has now written to David Cameron urging him to reconsider the “unsatisfactory” wording of the framework.

The trust’s remit, and the committee’s, is to protect the countryside. But the Government has a more urgent responsibility: to tackle the UK’s dismal housing record. There are now five million people on waiting lists, yet house-building is at its lowest peacetime level for 90 years. In the south-east of the country, house prices are now between eight and 12 times average annual incomes. Yet some local authorities do not appear to be making even a basic effort to see that local people have somewhere to live. The shortage of building land contributes to it. The authors of the framework were right to put the onus on local authorities to produce plans to help address the lack of housing.

It is true that we could be making better use of what is already there, such as the 300,000 empty dwellings. That would help, but we really do need more homes, and that means finding land on which to build them, and quickly.

This latest outbreak of opposition to reform of greenbelt laws from natural Conservative supporters is politically tricky.